Paper folding machines



n Oct. 14, v1958`4 c. B. RowLAND I 2,855,830

, PAPER FOLDING MACHINES Y Filed/Feb. 1, 195e v I 5 sheets-sheet` 1 A TTOVPNEV Oct. 14, 1958 c. BROWLAND 2,855,830

PAPER 'FOLDING MACHINES Filed Feb. 1, 195e A 5 sheets-sheet 2 IN VEN TOR.

A Trop/Ey Oct. 14, 1958 `c. B. RQWLAND 2,855,830

v PAPER FOLDING MACHINES Filed Feb. 1. 195e 5 Sheets-Sheet 3 INVENTOR.

ATTORNEY.

Oc't. 14,1958 y c. B. RowLAND 2,855,830

` PAPER FOLDING MACHINES Filed Feb. l, 1956 5 Sheets-Sheet 4 A T TOPNE Y Oct. 14, 1958 c. B. RowLAND 2,355,830

v PAPER FOLDING MACHINES Filed Feb. l, `1956 5 Sheets-Sheet 5 IN VEN TOR.

B y Yara H @wife/72a' C ATTQANEY PAPER FoLDlNG MACHINES Clare B. Rowland, Flint, Mich., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application February 1, 1956, Serial No. 562,719

This invention relates tofolding machines and more particularly to machines for folding lter paper into pleats of involute form.

In producing elements for filtering oils it is customary to wrap pleated lter paper around a perforated tube in such a way that each pleat is involute in form to gain a large filtering area. The space between adjacent and outwardly extending pleats is such as to have a large capacity for sludgei. e.-to be receptive to considerable sludge separated from contaminated oil before the useful life of the element is over. The clarified oil ows readily from between the contacting layers of paper in United States Patentl each pleat and into the perforated central tube for discharge. Such flow is possible because of the texture of paper usedr or radial grooves formed therein and the greater fluidity of the oil when clarified. An example of such involute type filter elements is disclosed in the United States application for Letters Patent Serial No. 409,361, filed February 10, 1954. (now Patent No. 2,801,009, dated July 30, 1957), in the name of Roy L. Bowers and entitled Filter Having Outwardly Extending Pleats. If such pleats are to be involute or curved in form after release from any constraint placed upon them, it creates a problem as to how such pleats should be folded. This problem is accentuated when it be realized that quantity production of the filter elements is the goal.

An object of the present invention is to provide a machine for folding work in the form of paper into discrete pleats each of which is curved; Another object is to provide a machine for folding paper into pleats and simultaneously stretching the paper so that each sideof each pleat is curved when released from constraint.

To the above ends, a feature of the present invention is a slotted base along which work in the form of paper may be fed in a given path, the base being combined with work clamping means at one side of a base slot, a movable shoe at the other side of the slot and a blade withdrawable by way ofthe slot and from between the shoe and the clamping means in timed relation with reciprocation of the shoe and actuation of the clamping means.

Anotherfeature is a staking blade and a reciprocable shoe each having rounded edges for stretching paper as the blade and shoe serve in forming pleats in the paper.

Another feature is a base for a folding machine handling paper to which paper adhesive may inadvertently be applied, the base being adapted to serve as a guide for the paper under motion and to contact the paper with a base surface material composed of polytetrauoroethylene.

A reciprocable blade is utilized in the embodiment of the invention disclosed to serve as a means for stretching the work, In the present specification and claims, this blade is referred to as a staking blade as it functions much the same as the staking blades commonly used in the'tanning industry for 'softening leather.

The above and other important features ofthe invention will now be described in detail in the specification and 2,855,830 Patented Oct. 14, 1958 rice then pointed out more specifically in the appended claims.

which is one embodiment of the present invention, parts being broken away better t0 illustrate the construction;

Fig. la is a front or work inlet end view of a portion of the machine shown in Fig. 1; p

Fig. 2 is an end view of a lilter element with a part of an end plate removed and disclosing the use of filter paper folded in the machine shown in Fig. 1; Y

Fig. 3 is a view of the rear or work discharge end of the machine looking in the direction of the arrows 3-3 in Fig. l with some portions being broken away;

Fig. 4 is a view of certain operative parts and looking in the direction of arrows 4--4 in Fig. 3;

Fig. 5 is a view of other operative parts, some of which are in section, looking in the direction of arrows 5-5 in Fig. 3;

Fig. 6 is a sectional view taken generally along the line 6-6 in Fig. 3;

Fig. 7 is an enlarged view of elements shown in Fig. 6 but shown in section;

Fig. 8 is a view of a cam mechanism looking in the direction of arrows 8 8 in Fig. 3; and

Figs. 9a to 9h show enlarged sectional views of structural details depicted in Fig. 1 and illustrating the positions assumed by the parts during consecutive steps of one operative cycle of the machine in forming an involute pleat in paper.

In Figs. l, la and 3, a folding machine representing one embodiment of the invention'is shown as being mounted or supported on a marginal portion of a table 10. The machine includes a horizontal base resting on the table top and this base consists of a main base plate 12 and a rear bar 14 spaced to define a vertical slot 16 extending across a work path. The bar 14 and slot 16 are so placed as to lie beyondthe edge of the table 10 and are connected to the bottom marginal portions of two vertical side plates 18 and 20. The rear edges of the latter are joined by a cross bar 21. Preferably, an extension platform 22 (Fig. l) is connected to or adjoins the rear of the bar 14 so that pleated work discharged from the machine may ow smoothly and be properly supported for subsequent handling. The platform 22 is not specifically described herein and is omitted from the showing in Fig. 2, but it should be appreciated that it may take any of various opposite parallel sides of the plate 12 is attached a guide bar such as the bar 24. These bars are attached to thev plate 12 by means of screws such as screws 26 and 28 and serve to define the path of the work between them as will further appear. The top of the plate 12 is provided with a groove 30 extending along the side of the bar 24. A similar groove 31 (Fig. 3) is formed on the plate 12 on the opposite side thereof.V Between the side grooves or the guide bars for the work the plate 12 is provided with three shallow grooves 32, 34 and 36 (Fig. 3) in which a special surface material 40 is placed. This material is retained in the grooves so that the top surface thereof is ilush with the top of the plate 12. The material is characterized by its lack of affinity for adhesives and is chemically defined as polytetrauoroethylene and is often called Teflon. In the drawings this material is so placed on the plate 12 as to terminate at the slot 16. If desired, the bar 14 and supplementary platform 22 may also be fitted with plastic inserts but such provision is not essential.

The upper surface of the bar 14 is provided with a groove 42 which s close to but spaced from the slot 16. This groove is in alignment with a vertical clamping blade 44 which is slightly tapered at its lower edge with half of the upper two corners attached to supporting a,sea,eso

blocks 4'6"a'nd"48'.'` The' blade' 44 is fixed to the blocks 46l and 48 by'means of`s'crews' 50 and 52; The opposite and vertical marginal portions of the blade 44 are retained and` guided in verticalA slots formed in verticalv guide pieces" Strand/581mg 3)' t'xe'd'to the inside snr'- faces of the two side plates 18 and 20. The blocks 46 and' 48are each" attached" by means. of 'screws such as the 'screws 60' (Fig. 5) to Vertical members 62 and 64. The latter" are simila'rin constriictiom' and, with respect ltothe member 64, it may be seenfrom Fig. that it includes a U-shaped mid-portion 66. A roller 68 is journ'aled`on afshaft'70iiir'edto-the member 64. This roller extend's'withiri ari endless cam slot 72 formed ina circularcam plate 74' joined to la second circular plate 76 by) n e'ansr ofserews'. 78. Another cam plate 80 is iXed to the other" side ofVv the plate 76 bymeans' of screws and the three p lates 74, 76 and 80'are centrally xed or keyed td'oiie endlof a horizontally mountedpower shaft 82;

The shaft 82 is m'ounted in a horizontal positionand rotatably/,supported on two vertical brackets 84 and 86 ired`to` a horizontal plate 88A which in turn rests upon and-ishXed to the upper edge ofthe. side plates 18and One"of"the"bearings for the shaft 82 `is depicted in Fig .-3.at One endy 92 of the shaftis-provided with akeyvtayY 94 so that a pulley maybe attachedthereto fondrivingthe shaft.

Next Yto thel verticalV memberV 62 are lthree plates 96, 98 and -100 which are joined together and are similar to' the plates 74, 76 and 80, as will be understood.

A's'th'e circular plates 100 and 80 are similarlalthough t the' opposite hand; the plate. 100-aloneisdescribed herein. This'plate is clearly shown in Fig. 4 and includes an endless camA groove 102 tov accommodate a roller1f0"4` mountedon a stub-shaftl 106 fastened to av vertical-member 108'. An intermediate portion of the latter. is'U-shaped as at 110ito av'oidvthe shaft 82. The lower end of the member 108 extends downwardly and helwthe base plate 12 andis attached by means of screws '11' '2`to' one endV ofa horizontal barY 114. The` other end of`thebar isxed by means of screws 116 to the lowerendof.- a Vertical.. member 1-18 similar to the member 108" and carrying aroller 119- cooperating with the 'cam disc8-0'.

A ,verticali stal 'ing, bladeV 120`V is slidably/ retained With in the slot 16' and. is. provided. with. three depending tongues. 122,]1'24 and-126' (Fig. 3). Each of thesetohgn'e'sis xed by means of ar screw 128 to the bar 114.

Ortwnrdly.- extending.from eachrof. the vertical vbrackets. 84 andf`86 andlat thevtop thereof is-xed a horizon#Y tall bracket 130; Each.of-..these horizontal brackets is provided'with a suitableanti-frietion or roller arrangement`132' for maintaining.thevertical members such as and 11'8`or 62 and 108 against lateral displacement. Specic details regarding'- this roller arrangement are noti'describe'd herein as it is obvious that other guiding means maybe provided permitting Vertical reciprocation of the vertcalfmembers referred to and as will appear as the description proceeds.

Itlwill be notedinfFig. 1-that the work guide strips, suchasthe'metal side strip24, terminate a considerable distanceffrom the base slot16.y Between the rear ends of the *guide stripsand theslot a: shoe 134l is provided and suhcient'space exists ybetween the strips and the slot so that the shoe may be moved= or reciprocatedy in a` horizontal directionvtowardr andaway from the slot 16. The bottomsurface-.135of theshoe1134 is spaced a shortdistance from-the top surfaceof the base plate 12 and the Teonfstripsf40, and-this space is maintained by causingthe extremeendsof the shoe 134-to rest upon suitable guide bars such as the bar 137 placed in alignment with the work feed lguidestrips and partially shown in Figs. 92z to 9h`. The shoe 134 extends from one side plate 1'8 to the other side plate 20 and isi L-shaped in cross-section. The lower rearward'edge ofthe-shoe 134- is rounded oi as at 136 and the rearl upper edge is cen- 4,- trally recessed a short distance as" at 138 to accommodate a tilting blade-'140. The latter is pivotally mounted on the shoe by means of a shaft 142. The recess 138 has an inclined upper wall portion permitting the upper half of the blade 140 to swing forwardly when occasion demands, as will further appear. The lower portion of the blade 140, while in its normalposition, lies iiush with the rear surface of the shoe 134. This normal position is retained by'two spring and plunger arrangements 144 one ofl which is shown in Fig. 7. Eachplunger arrange'- ment includes af rod 146`withV a rounded end bearing against the blade 140 above the shaft 142. Thero'd is slidably mounted in the upper portion of the shoe 134. A spring 148 is held in a recess 150 formed in a block 152 suitably fixed to the horizontal portion of the shoe 184 as by screws such as screw 149. A screw 153 serves as a seat for one end of the spring 148. The horizontal portionof the shoe 134 also supports a U-shaped bracket 154' which is` ofpioperproportionto receive a' cylinder I156 iiXed as an integral partto the lower end ofa lever" 158. This lever is pivotedon astationafry`pini160 and is provided atitsu'pper end with a stiibshaft 162 supporting Ia roller 164. The latferextendswithin an endless cam' slot'166 formed in a 'circular' cam disc 168. This dis'chas' a h'ub 169'and' is xed to a base disc 1-70 and the-'two discs and hub forni an assembly joined to the shaftV 82for`rotation therewith. The pin 160 is mounted on suitable blocks such as the block 165. These-blocks lare li'xed to the topl surface ofY the horizontal plate 88 respectively,.and the pins are mounted on brackets 182- and 184 xed to the plate`88. Each of the brackets 182 and 184 have upstanding side portions between which the corresponding lever 174u or 176 may o scillate. The upper end of each of the levers 174 and 176 is provided with a roller 186 or 188 engaging a cam 190 or 192 fixed to the shaft 82.

From the above, it shouldnbe notedthat the. outside pair of cam discs andf100 mayfserveto operate the' staking. bladeV The" inside p airofcamdiscs- 74 and 96'rnay operate the clampingblade 44 The inside cam disc 168-170 assembly is-connected tothe sliding shoe 134 and the two inside cams190 and 192 are associatedwith the tilting blade 140.

-In the operation of the machine, paper'Y is-fed from the left end of the machine, as the latter is Viewed in Fig. 1. T he paper is directed along the upper face of the plate 12 with its path determined by the side guide-strips such as the strip 24. When making a pleatedflter element, the paper is yintroduced with-adhesive lOnits. marginalV undersideportions. In order to operate the machine it -is essential that the shaft 92 .be rotated .by some suitable power means and that the-paper be introduced along the plate 12 and over the Teflon strip 40 and through `the space defined by the plate 12 andthe-shoe 134. Operation on the work begins when the clamping blade 44is caused to assume the position, as shown in Fig. 9a, to clamp a narrow transverse portion of the paper against the bar 14. Because of the-action of the outside cam discs y80 and 100, the' staking blade 120 isfcausedgto rise fromits lowered position to a position betweenfthe shoe 134- and the blade- 44, asseen in Fig. 9b. As a result, the paper W is fed rearwardly from between the shoe 134-and-the plate12 .andthe paper istA staked or stretched by frictional contact with the' rounded upper edgel of: the blade- 120 and the rounded edge 136 ofthe shoe'. In this manner the paper is stretchedl 'tz-gebotene infsuh 1a way as to iformI curvedfpleat fs'ides, fasthown :1in the `completed tproduct, and Snicientgpaper f T'is fed to makeupl one loop for onepleatl g The 'blade'120 `vflill'then lowerl andthe shoe 134=fbegins ltoproceedtrearwardlywith the loop having Apermanently vcurved and stretched sides, Ias'depicted in Fig. `9c. The f'shoe 134:,continues its rearward motion to 'clamp ior foldtherpleatfagainstthelclamping blade 44, -as kseendn Fig.9d. ltwill-b'elnoted thatat this stageithe itiltingbla'de 140 vand '.the levers`174 kand 176 .interengage ibut 'are :of nofeffect. In the event that adhesive has vbeen appliedtolthemarginal-'underside portions of .the work-W, lthe .pleat will 'remain tightly folded after release and,becauseioffthepreviousstaking action, the pleat will be curved, as depicted in Fig. 9e. Release of the pleat is gained "bya forward motion 4of rthe shoe 134 and then an `upwardm'otion ofthe blade 44. The motion .ofthe shoe 134 is accompanied with an ,action by the cams 190 and 192 through theilevers 17'4 and176 to pivot the tilting blade 140 and urge the nished pleat upwardly. As a result of this completed action, the clamping blade 44 and shoe 134 are positioned to begin forming of the next discrete pleat, as seen in Fig. 9f. Blade 44 is now caused to lower and again clamp the work against the bar 14-i. e.-blade 140 permits entry of the blade 44 between the shoe and the pleat, as shown in Fig. 9g. After this, the shoe 134 continues its forward motion and the machine parts are again positioned, as shown in Fig. 9a or 9h, but with the finished pleat on -the discharge side of the clamping blade 44, as shown in Fig. 9h.

From the above description, it may be seen that a machine has been provided for forming discrete pleats of curved form from a strip of paper and to perform its functions accurately and efficiently as required in volume production. In the event adhesive is used on the under marginal side of the paper, the side grooves such as the groove 30 prevent contact of the .adhesive with the base plate 12 so that it does not interfere with feeding of the work. The Teflon strips 40 safeguard against the sticking of any adhesive which may inadvertently be placed on portions of the paper intermediate its margins. With a smooth feeding of the work, the paper need not possess an unduly high strength in tensions. The staking action on the paper ensures proper curvature of the pleats whether or not an adhesive is used. In some uses of the machine it is clear that adhesive may be applied t-o the paper :after it is pleated and not before.

In Fig. 2 the filter element is of the type disclosed in the application Serial No. 409,361 (now Patent No. 2,801,009) earlier referred to. It comprises two circular and apertured endplates A and B connected by a perforated tube C around which is wound a strip of filter paper folded into a multiplicity of outwardly extending `and annularly spaced pleats D. The involute form of each pleat is due to the folding technique employed in ythe use of the machine herein disclosed. The end margins at the interface of the two layers in each pleat D are joined by an adhesive which aids in the assembly but such adhesive is not necessary, as stated above, in the operation of the machine for the securing of properly curved pleats.

I claim:

1. A folding machine comprising a base presenting a plane surface along which work in the form of paper may be fed, a slot extending through said base, :a groove extending along said surface parallel with and on one side of said slot, a shoe facing said surface on the other side of said slot, a staking blade slidably mounted in said slot and having a rounded edge parallel with said surface, a clamping blade with a clamping edge aligned with and facing said groove, said rounded edge and clamping edge facing opposite directions, and means for actuating said blades and shoe in timed relation to effect clamping of work between said clamping blade and groove, formation of a loop in said work between said '6 clamping blade "and'sad shoe Lby said staking blade, Aand clampingof said loop between said shoe and clamping blade after `said staking blade `is withdrawn ifromwithin said'- loop.

2. foldingmachine comprising =a base 'along Vwhich Work-1n the 'formffpaper may be Afed in a given "path, a slotfextendiug through Lsaidbase, 'a shoe `facingsai'd base atrend-side yo'f said --slot and reciprocable along 'said path,

l azstakingblade slidably mounted in said slotfor reciprocablefmotion transversefto said path, `clamping means at the othenside of said slot, andme'ans for actuating said clamping' means, lshoe-and istaking-blade :in timed relation tozform discrete pleats irrsaid-paper.'

`ttzffolding machine comprising 4a base along v`which work `.in :the 'form Iof lpaper l-may be -fed in va given .path, said base being provided with '-a surface of polytetratiuoroe'thylene, afslotcxtendingthroug'h saidbase, a shoe facing said ibase fat one tsideof said slotA and reciprocable along but in spaced relation with said path, a staking blade slidably mounted in said slot for motion transverse to said path, work clamping means at the other side of said slot, and means for cooperatively `actuating said work clamping means, shoe and staking blade in timed relation to form discrete pleats in paper introduced between said shoe and base.

4. A folding machine comprising a base along which work in the form of paper may be fed ina given path, a slot extending through said base, a shoe facing said base .and spaced Vtherefrom at one side of said slot and reciprocable al-ong said path, a tilting blade pivoted on said shoe, .a staking blade slidably mounted in said slot for motion transverse to said path, work clamping means at the other side of said slot for clamping work introduced between said shoe and base, and means for cooperatively actuating said work clamping means, shoe staking blade `and tilting blade in timed relation to form discrete pleats in said paper.

5. A folding machine comprising a substantially horizontal base along which work in the form of paper may be fed in a given path, a slot extending through lsaid base,

a shoe facing said base but spaced therefrom at one sidev of said slot and reciprocable along said path, a staking blade slidably mounted for motion from said slot and across said path, work clamping means at the other side of said slot to clamp work fed between said shoe and base,

and cam means above said base connected to said work clamping means, shoe and staking blade cooperatively to,

actuate the said means, shoe and blade in timed relation to form discrete and stretched pleats in said paper.

6. A folding machine comprising a base along which work in the form of paper may be fed in a given path, a slot extending through :said base, a shoe facing said base but spaced therefrom at one side of said sl-ot and reciprocable along said path, a staking blade slidably mounted in said slot for reciprocable motion and transverse to said path, a clamping blade at the other side of said slot and arranged to cooperate with said base to form a work clamp, means for actuating said clamping blade shoe and staking blade in timed relation to form discrete pleats in said paper, and said clamping blade and shoe having rounded edges for engaging opposite sides of said paper.

7. A folding machine comprising a base along which work in the form of paper may be fed in a given path, a slot extending through said base, a shoe facing said base but spaced therefrom at one side of said slot and reciprocable along said path, clamping means at the other side of said slot to clamp work fed from between said shoe and said base, a staking blade slidably mounted in said slot for movement into and away from the space between said shoe and clamping means, means for actuating :said clamping means, shoe and staking blade in timed relation to form a discrete pleat in said paper, and said staking blade being arranged to form a loop in the paper while said clamping means is effective and therebyfeed sufficient paper for one pleat from between the said shoe and base.

8. A folding machine comprising a substantially horizontal base along which work in the form of paper may be fed in a given path, a slot extending upwardly through said base and across said path, a shoe facing said base but spaced therefrom at one side of said sl-ot and reciprocable along said path, a staking blade extending upwardly into said slot and vertically reciprocable therein for motion transverse to said path, Work clamping means comprising a blade and a grooved portion in said base aligned with said blade and arranged at the other side of said slot, a polytetrauoroethylene surface onv said baseand cam means arranged above said base for actuating said work clamping blade, shoe and staking blade intimed relation to form discrete pleats in said paper.

9. A folding machine comprising a substantially horizontal base along the top surface of which work in the form of paper may be fed, said base having a substantially vertical slot therein and extending in a plane transverse to the path of said work on said surface, a shoe over said surface -on the in-feed side of said slot and horizontally reciprocable along said path, a staking blade in said slot with its upper edge vertically reciprocable immediately above sadfslot, work clamping means arranged on the work-discharge side vof said slot, and means for actuating said work clamping means and staking blade in timed relation with the horizontal reciprocating movement of said shoe to stress the work between the said shoe aud blade and form curved and discrete pleats in the paper and thrust them along said path for discharge.

References Cited in the file of this patent UNITED STATES PATENTS 1,480,947 Mauer'. Jan. is, 1924 

